Thousands of flights in the UK have been cancelled following a major error in the IT system of the nation’s air traffic controller.

The majority of the disruption took place Tuesday, when more than 1,900 flights were cancelled. Nats, a public private partnership in charge of managing the UK’s airspace, revealed in a statement that its flight processing system was at fault.

The technical issue has since been fixed, but spokespeople for airports including London’s Gatwick and Heathrow have said on social media that disruptions are likely to continue for parts of today. Nats said in a statement that it had been a “very complex recovery”.

This is the third major flight disruption caused by Nats in as many years. A spokesperson for the company said that the cause of the disruption was not the same as those in 2023 or 2025.

On BBC Radio 4’s Today programme, Nats chief executive Martin Rolfe ruled out a cyber attack as the cause of the disruption, adding that it will be doing a “very, very thorough” investigation.

“Inevitably things to go wrong in complex systems, we never want them to, we hope they don't, but we absolutely plan for them,” Rolfe added.

He told the programme that Nats had invested more than £1 billion in technology over the past 25 years, and consistently improved its services “from a very good base”.

Despite this, Rolfe has been summoned by the UK’s transport secretary, Heidi Alexander, and will meet with her later today. Alexander wrote on X that she will be “seeking assurances that lessons will be learned”.

The disruptions have also intensified calls for Rolfe to resign, with aviation leaders including Ryanair’s chief operations officer and Wizz Air’s UK head suggesting he should consider his position.

Nats did not respond to a request for comment by National Technology News on the specifics of the failure.

Nats was originally created in the 1960s as a way to bring unify air traffic control for the UK’s civil and military aviation, but has operated as a public-private partnership since 2001. Under this structure, the government owns 49 per cent of the company but also holds a golden share, meaning it retains the power to outvote other shareholders in specific circumstances.

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